Vertical Power VP/X Issue?

[dweyant]

I did first flight on my RV-14A today (N96KW). Overall things went well, and it flew quite nicely!

However, like all first flights (this was my 12th). There are a few things that need addressing. Most significant is a pitch trim issue.

During flight the pitch trim stopped working. It blew the breaker, I reset it, and as soon as I tried to move the trim it would blow again.



After I landed, I tried to recreate the issue. I could get the trim to run (no blown breaker) but it would only run in one direction, and at a very slow speed.



After some troubleshooting, we determined.



The trim servo (Ray Allen) works fine. Putting 12 Volts directly to it runs the motor in both directions as you would expect.



The VP/X is only putting out 10.2 volts to the Servo (reported as 12.4 volts at the battery and via the VP/X

Only 2.5 volts is recorded when the servo motor is hooked up and running (very slowly)

The VP/X is only putting out voltage in one direction. I.e. the Grey and White wire are no longer switching direction. It does not matter if the trim is activated from either stich, the screen, or the PC connected to the VP/X



The trim worked normally and in both directions before the flight. We had a loose wire (crimp) that was corrected. Trim servo was run all the way in both directions several times to test.



Any suggestions you have for troubleshooting would be greatly appreciated.


VPX log attached in case anyone wants to try and decipher...

Thank you,



-Dan

 

[Radomir]

wiring.. that's first thing that comes to mind that would possibly explain the situation..

 

[JeremyL]

Have you found any resolve to this?

 

[Brantel]

Contact Chad at VP. He is pretty good at resolving issues.
@cjensen

 

[dweyant]

Yes, it was a bad VP/X unit.

-Dan

 

[pilotkms]

Yes, it was a bad VP/X unit.

-Dan

Can u provide info on the repair/replacement of the VPX?

 

[dweyant]

Can u provide info on the repair/replacement of the VPX?

It was basically a brand new unit (less than an hour flight time).

Vertical Power did replace it with a new unit, however I was quite disappointed in the time it took. Contacted them on a Saturday, heard back from them on Monday, determined within a couple hours that it was a bad unit.

Initially they offered to ship a loaner unit “maybe” on Friday if they got one back. I pushed for a replacement, which they finally agreed to, but it took until Thursday afternoon to get the unit shipped out overnight.

The very good news is it fixed the problem and I was able to put another almost three hours on my RV-14A before I had to leave for a business trip.

-Dan